Circuits

Question 1

What is this circuit component? What does it measure? Where should it be placed?

Answer 1

This is an ammeter. It measures current in amps. It should always be in series.

Question 2

What is this circuit component? What does it measure? Where should it be placed?

Answer 2

This is a voltmeter. It measures p.d. in volts. It should always be placed in parallel around a component.

Question 3

What is this circuit component?

Answer 3

A cell

Question 4

What is this circuit component?

Answer 4

A bulb (or any light source)

Question 5

What is this circuit component? What does this component do?

Answer 5

This is a resistor. It adds a fixed amount of resistance to the circuit.

Question 6

What is this component? What does it do?

Answer 6

This is a light emmitting diode (LED). In the same way as a diode, it only allows current to flow in one direction, however an LED emits light when it conducts.

Question 7

What is this component? What can it be used for?

Answer 7

This is a variable resistor. It can be used to vary the current in a circuit to a minimum when investigating characteristics of different components.

Question 8

What is this circuit component? What does it do? Where can it be used?

Answer 8

This is a diode. It only allows current to flow in one direction. The direction in which the diode conducts is referred to as its ‘forward’ direction. Examples of the use of diodes include the protection of dc circuits (in case the voltage supply is connected the wrong way round), and rectification (changing ac to dc).

Question 9

What is this circuit component? How does its function change?

Answer 9

This is a thermistor. Its resistance decreases withj increasing temperature.

Question 10

What is this circuit component? How does its function change?

Answer 10

This is an LDR. Its resistance decreases with increasing light intensity.